The invention relates to a plastic sealing plug or cover especially intended for the closing and sealing of an opening in a panel member. The cover is of the type including a bottom part having an adjoining sealing lip adapted to lie against the upper side of the panel, and a sealing catch ring lying opposite the sealing lip and pressing against the under side of the panel. The panel member may be, for example, a motor vehicle body or frame part or a component of a household appliance.
As state of the art, a sealing cover of this general type is already known in which the catch ring cooperates in sealing only over a short contact distance with the under side of a panel (see, for example, West German Patent No. 3,446,151). Along with an insufficient sealing effect, there is given accordingly an insufficient automatic centering of this known sealing cover.
The present invention attacks, therefore, the problem of providing a sealing cover of the kind mentioned, in which, besides good centering there is assured, most importantly, the fullest possible sealing of the carrier opening.
This problem is solved, according to the invention, by the fact that the catch ring has two sealing surfaces which engage tightly against the opposed surfaces of the panel in the zone of the opening. This gives the advantage that the sealing cover seals over sealing surfaces of the panel on both sides of the panel opening. Thus, the cover, besides having a good centering, is absolutely watertight.
In a further development of the invention, the catch ring may have a circumferential protrusion and a sealing flange lying opposite this protrusion. Here, additionally, the zone of the catch ring between the surrounding protrusion and the sealing flange may be set to the diameter of the panel opening. This produces, advantageously, a triple sealing of the panel opening through the sealing cover according to the invention; namely, one seal from the upper side of the carrier opening, a second seal from the lower side of the panel opening, and a third seal in the zone of the end wall of the panel opening itself.
According to another feature of the invention, the sealing flange may consist of a horizontal portion and a further portion directed diagonally toward the panel opening, so that a good resilient sealing effect is assured.
In a further development of the invention, the sealing flange is arranged in the zone of the sealing lip, while the sealing lip covers the sealing flange and the protrusion of the catch ring.
According to another feature of the invention, the zone of the catch ring which is fitted to the carrier opening is arranged to strike against at least one edge of the carrier opening. In this way, there is produced a further improvement of the sealing effect. Preferably, the surrounding protrusion on the side opposite the sealing flange is designed with beveled surface located to strike against an edge of the panel opening to thus further improve the sealing effect.
In a further development of the invention, a diagonally remaining stay may join the catch ring to the bearing crown of the closing cover.
In a further development of the invention, it is also possible to produce the sealing cover, for example, as a composite from two or more materials. Here, a softer component can be used for the sealing of the panel, and a harder component can provide strength. The harder material of the bottom part may, for example, be provided with a basic configuration which is advantageous for fully automated installation. Various geometric figures in the form of stays may be placed in the basin.
As an alternative to the basin configuration in the zone of the bottom part, the latter may also be provided with a smooth closure wall.
The joining of the composite, plural component structure may take place in a multi-component injection molding process. As an alternative, it is also possible to join, for example, the bottom part and the catch ring together through several pins, knobs or protrusions, so that there is a mechanical connection between the two parts of the sealing cover according to the invention.
Through the special shaping of the sealing cover, it is also possible to place the latter in greatly deformed bores or in panels with collar holes. In this way, the sealing cover according to the invention, may be mounted from below. There is given, advantageously, a water-tightness and a protection against a stone blows from outside as well as sufficient strength from the inside to support walking loads.